NASA's Heliophysics Gallery

After launch, the James Webb Space Telescope will travel to its orbital destination. Webb will perform its science mission while orbiting a location in space, called the second Lagrange point, or L2 for short. L2 is located one million miles from Earth. As Webb orbits L2, the telescope stays in line with Earth as it travels around the Sun. L2 is a point where the gravitational influences of the Earth and Sun balance the centripetal force of a small object orbiting with them. The telescope's optics and instruments need to be kept very cold to be able to observe the very faint infrared signals of very distant objects clearly. This location is perfect for Webb's sunshield to block out light and heat from the Sun, Earth, and Moon. Unlike the Hubble Space Telescope, Webb's orbit keeps the spacecraft out of the Earth's shadow making L2 a thermally stable location for the observatory to operate at. Webb will operate within its field of regard. The "field of regard" refers to the angles the telescope can move while staying in the shadow of the Sun. Each of Webb's instruments has its own field of view. The field of view is the area of sky an instrument can observe. Webb's fine steering mirror is moved so that an object can be observed by the different instruments. This prevents the whole telescope from having to repoint itself to do so. The Webb Telescope’s commissioning process will be complete approximately six months after launch, at which time Webb start its science mission. Helping to uncover more of the mysteries of our Universe.

The Sun emitted a mid-level solar flare on Jan. 20, 2022, peaking at 1:01 a.m. EST. NASA’s Solar Dynamics Observatory, which watches the Sun constantly, captured an image of the event. Solar flares are powerful bursts of energy. Flares and solar eruptions can impact radio communications, electric power grids, navigation signals, and pose risks to spacecraft and astronauts. This flare is classified as a M5.5 class flare. More info on how flares are classified here. To see how such space weather may affect Earth, please visit NOAA’s Space Weather Prediction Center https://spaceweather.gov/, the U.S. government’s official source for space weather forecasts, watches, warnings, and alerts. NASA works as a research arm of the nation’s space weather effort. NASA observes the Sun and our space environment constantly with a fleet of spacecraft that study everything from the Sun’s activity to the solar atmosphere, and to the particles and magnetic fields in the space surrounding Earth.

The solar 'constant', the amount of energy received from the Sun during the course of the 11 year solar cycle, is not strictly constant. There is small variation during the course of the cycle due to the change in solar activity. Sunspots form in regions with stronger magnetic fields on the photosphere and appear dark against the hotter solar surface, even though they are still quite hot. Faculae are extended regions that tend to form around sunspots and are hotter, and brighter, than the photosphere. Faculae are barely visible in solar imagery taken in visible light, but are more obvious in specific wavelengths (such as 1700 Angstroms used here) as the brighter speckled regions around many of the sunspots. The hotter and more extended area of the faculae add more to the solar energy output than is taken away by the cooler and smaller sunspots, yielding a slight net increase in the solar luminosity around solar maximum.

For the first time in history, a spacecraft has touched the Sun. NASA’s Parker Solar Probe has now flown through the Sun’s upper atmosphere – the corona – and sampled particles and magnetic fields there. As Parker Solar Probe flew through the corona, its WISPR instrument captured images. The Wide-Field Imager for Parker Solar Probe (WISPR) is the only imaging instrument aboard the spacecraft. WISPR looks at the large-scale structure of the corona and solar wind before the spacecraft flies through it. About the size of a shoebox, WISPR takes images from afar of structures like coronal mass ejections, or CMEs, jets and other ejecta from the Sun. These structures travel out from the Sun and eventually overtake the spacecraft, where the spacecraft’s other instruments take in-situ measurements. WISPR helps link what’s happening in the large-scale coronal structure to the detailed physical measurements being captured directly in the near-Sun environment. To image the solar atmosphere, WISPR uses the heat shield to block most of the Sun’s light, which would otherwise obscure the much fainter corona. Specially designed baffles and occulters reflect and absorb the residual stray light that has been reflected or diffracted off the edge of the heat shield or other parts of the spacecraft. WISPR uses two cameras with radiation-hardened Active Pixel Sensor CMOS detectors. These detectors are used in place of traditional CCDs because they are lighter and use less power. They are also less susceptible to effects of radiation damage from cosmic rays and other high-energy particles, which are a big concern close to the Sun. The camera’s lenses are made of a radiation hard BK7, a common type of glass used for space telescopes, which is also sufficiently hardened against the impacts of dust. WISPR was designed and developed by the Solar and Heliophysics Physics Branch at the Naval Research Laboratory in Washington, D.C. (principal investigator Russell Howard), which will also develop the observing program.

Starting Dec. 3, we took a journey from Earth to the Sun. We made pit stops along the way to learn how the Sun influences everything in the solar system. In 2018, NASA launched Parker Solar Probe to study the Sun up close. But the mission has also taught us much more about our solar system. On the final day of the #SolarTour, we had big news to share: Parker Solar Probe officially “touched” the Sun, becoming the first spacecraft in history to fly through the solar atmosphere. Below are postcards we released at each pit stop of the Solar Tour campaign.

On recent solar encounters, Parker Solar Probe collected data pinpointing the origin of zig-zag-shaped structures in the solar wind, called switchbacks. The data showed one spot switchbacks originate is at the visible surface of the Sun – the photosphere. By the time it reaches Earth, 93 million miles away, the solar wind is an unrelenting headwind of particles and magnetic fields. But as it escapes the Sun, the solar wind is structured and patchy. In the mid-1990s, the NASA-European Space Agency mission Ulysses flew over the Sun’s poles and discovered a handful of bizarre S-shaped kinks in the solar wind’s magnetic field lines, which detoured charged particles on a zig-zag path as they escaped the Sun. For decades, scientists thought these occasional switchbacks were oddities confined to the Sun’s polar regions. In 2019, at 34 solar radii from the Sun, Parker Solar Probe discovered that switchbacks were not rare, but common in the solar wind. This renewed interest in the features raised new questions: Where are they coming from and how do they form and evolve? Were they forged at the surface of the Sun, or shaped by some process kinking magnetic fields in the solar atmosphere? The new findings, in press at the Astrophysical Journal, finally confirm one origin point near the solar surface. More information here.

For the first time in history, a spacecraft has touched the Sun. NASA’s Parker Solar Probe has now flown through the Sun’s upper atmosphere – the corona – and sampled particles and magnetic fields there. The new milestone marks one major step for Parker Solar Probe and one giant leap for solar science. Just as landing on the Moon allowed scientists to understand how it was formed, touching the very stuff the Sun is made of will help scientists uncover critical information about our closest star and its influence on the solar system. More information here.

For the first time in history, a spacecraft has touched the Sun. NASA’s Parker Solar Probe has now flown through the Sun’s upper atmosphere – the corona – and sampled particles and magnetic fields there. The new milestone marks one major step for Parker Solar Probe and one giant leap for solar science. Just as landing on the Moon allowed scientists to understand how it was formed, touching the very stuff the Sun is made of will help scientists uncover critical information about our closest star and its influence on the solar system. On April 28, 2021, during its eighth flyby of the Sun, Parker Solar Probe encountered the specific magnetic and particle conditions at 18.8 solar radii (8.127 million miles) above the solar surface that told scientists it had crossed the Alfvén critical surface for the first time and finally entered the solar atmosphere. More information here.

NASA’s Parker Solar Probe has now done what no spacecraft has done before—it has officially touched the Sun. Launched in 2018 to study the Sun’s biggest mysteries, the spacecraft has now grazed the edge of the solar atmosphere and gathered new close-up observations of our star. This is allowing us to see the Sun as never before—including the findings in two new papers, which were presented at AGU, that are helping scientists answer fundamental questions about the Sun. PANELISTS Dr. Nicola Fox • Heliophysics Division Director of the Science Mission Directorate at NASA Headquarters Dr. Nour Raouafi • Project Scientist for NASA’s Parker Solar Probe • The Johns Hopkins Applied Physics Laboratory Dr. Justin Kasper • Principal Investigator for Solar Wind Electrons Alphas and Protons (SWEAP) Investigation on Parker Solar Probe • BWX Technologies, Inc., University of Michigan Prof. Stuart D. Bale • Principal Investigator for Fields Experiment (FIELDS) on Parker Solar Probe • University of California, Berkeley Dr. Kelly Korreck • Program Scientist at NASA Headquarters • Smithsonian Astrophysical Observatory

The Sun's corona extends far beyond the solar surface, or photosphere and is considered the outer boundary of the Sun. It marks the transition to the solar wind which moves through the solar system. This limit is defined by the distance at which disturbances in the solar wind cannot propagate back to the solar surface. Those disturbances cannot propagate back towards the Sun if the outbound solar wind speed exceeds Mach one, the speed of 'sound' as defined for the solar wind. This distance forms an irregular 'surface' around the Sun called the Alfvén surface. Parker Solar Probe has now reached close enough to the Sun that it has begun to penetrate this Alfvén surface. From measurements of the solar wind plasma environment by the Parker's FIELDS and SWEAP instruments, scientists can compute the 'speed of sound' for the plasma, which exhibits brief periods when the Mach number drops below unity (one). At Parker's distance during encounter 8, the Mach number dropped below unity on several occasions. Propagating the magnetic field vector at Parker back to the solar photosphere revealed that these regions corresponded to significant changes in the magnetic field on the photosphere, particularly that fields lines of 'open' magnetic flux were transitioning from one location to another. In the visualizations below, we see the measured Mach number at Parker propagated along the orbit, with green representing Mach number greater than one, grey represents Mach number approximately one, and red represents Mach number less than one. When we trace the field lines at these moments back to the Sun, we see the field line jumping between isolated regions of 'open' magnetic flux - blue for inward magnetic flux and red for outbound magnetic flux.

For a number of years, solar scientists have known about a phenomenon they called 'switchbacks'. Switchbacks are short-term 'flips' in the polarity of the magnetic field in the outflowing solar wind. Parker Solar Probe has detected these 'switchbacks' (Switchbacks Science: Explaining Parker Solar Probe’s Magnetic Puzzle), which appear to be more plentiful closer to the Sun. In the visualization above, Parker is passing through a region of inward bound magnetic flux (blue lines). This surrounding field is computed from a running average of the measurements by Parker, which are computing from the individual measurements at Parker's position (arrows projecting from the spacecraft position). For a brief time, these vectors flip direction, in this particular case changing color from blue to white and red, from the surrounding field, which is the signature of a switchback. Closer to the Sun, the average field lines trace back to coronal structures called pseudostreamers, that are magnetic structures which overlay and connect multiple pole magnetic regions. These regions also appear to correlate with where magnetic flux emerges between supergranule convection cells.

Using observations from NASA’s ICON mission, scientists presented the first direct measurements of Earth’s long-theorized dynamo on the edge of space: a wind-driven electrical generator that spans the globe 60-plus miles above our heads. The dynamo churns in the ionosphere, the electrically charged boundary between Earth and space. It’s powered by tidal winds in the upper atmosphere that are faster than most hurricanes and rise from the lower atmosphere, creating an electrical environment that can affect satellites and technology on Earth. The new work, published today in Nature Geoscience, improves our understanding of the ionosphere, which helps scientists better predict space weather and protect our technology from its effects. More information: https://www.nasa.gov/feature/goddard/2021/strong-winds-power-electric-fields-in-upper-atmosphere-icon/

Formally the Radiation Belt Storm Probes (RBSP)

While the sun is well known as the overwhelming source of visible light in our solar system, a substantial part of its influence is driven by some aspects less visible to human perception - the magnetic field.

Solar Cycle 25 has begun. The Solar Cycle 25 Prediction Panel announced solar minimum occurred in December 2019, marking the transition into a new solar cycle. In a press event, experts from the panel, NASA, and NOAA discussed the analysis and Solar Cycle 25 prediction, and how the rise to the next solar maximum and subsequent upswing in space weather will impact our lives and technology on Earth.

The Earth's magnetic shield

The near-Earth space enviroment is a complex interaction between Earth's magnetic field, cool plasma moving up from Earth's ionosphere, and hotter plasma coming in from the solar wind. This interactions combine to maintain the radiation belts around Earth.

Earth isn't the only solar system body with an internally generated magnetic field. Here are some visualizations of simplified versions of magnetospheres of the giant outer planets.

For over 40 years, NASA's Sounding Rocket Program has provided critical scientific, technical, and educational contributions to the nation's space program and is one of the most robust, versatile, and cost-effective flight programs at NASA.

On Monday, May 9, 2016, Mercury will transit across the sun. This rare event will begin at 7:11 AM EDT and will continue for more than seven hours. NASA's Solar Dynamics Observatory will watch this transit from start to finish, ultra high definition images of the event in near real time as it unfolds. This is the first time SDO has captured this transit, which hasn't occurred since 2006. It won't occur again until 2019. NASA Scientists use the transit method to learn more about planets both in our solar system and beyond. Scientists can monitor the brightness of stars, looking for dips in that brightness that signal a transiting planet. Using the transit method, scientists can determine the distance of these planets from their stars, as well as their size and composition. Upcoming missions like the Transiting Exoplanet Survey Satellite will use the transit method to search for planets orbiting nearby stars.

This gallery contains visuals in support of the June 5, 2012 transit of Venus across the solar disk.

Orbits and trajectories of many missions observing the Sun and the near-Earth environment.

The sun is always changing and NASA's Solar Dynamics Observatory is always watching. Launched on Feb. 11, 2010, SDO keeps a 24-hour eye on the entire disk of the sun, with a prime view of the graceful dance of solar material coursing through the sun's atmosphere, the corona.

SDO, the Solar Dynamics Observatory, images the entire sun at 4096x4096 resolution in multiple wavelengths every 12 seconds. The selection below represents some of the best options for full-disk slow rotation. The 4k content is available for download as frame sequences, and, in some cases, as ProRes video. These files are large and will take a long time to download.

Solar flares! CMEs! The Really Big Images from Solar Dynamics Observatory! Get them here!